Friday’s Homework 1. Any questions? 2. Make sure the homework is 100% complete. • Incomplete work will NOT be accepted. Factoring Polynomials 4/7/2015 Factoring by GCF Objective: factor polynomials by taking out the GCF. Students apply basic factoring techniques to second-and simple third-degree polynomials. These techniques include finding a common factor for all terms in a polynomial, recognizing the difference of two squares, and recognizing perfect squares of binomials. Notes • Prime Number = a whole number greater than 1 that has exactly two whole numbers as factors, itself and 1. • 2, 3, 5, 7, 11, … • Prime Factorization = All of the prime factors of a number. • Hockey Stick Method 1. Write an upside-down division sign. 2. Determine a prime-factor (2, 3, 5, 7, 11,…). 3. Write the factor in front of the division sign and place the quotient below. 4. Repeat until complete. 5. Write the prime factorization (the hockey stick). Notes Now you try. Write the prime factorization. Ex. Ex. Ex. - Upside Down 9 0 Division 2 60 2 8 4Division- Upside 2 Down - Try 2, 3, 5, 11, … - Try 2, 33, 5, 4 57, 11, … 2 30 2 7,42 - Anything else? - Anything 15 3 15 3 21 3 else? - Draw Hockey 7Stick - Draw Hockey 5 5 Stick PF 2 2 3 5 PF 2 2 3 7 PF 2 3 2 5 Notes • Greatest Common Factor (GCF) = the highest factor of two or more numbers. Find the GCF. Ex. Now you try. Ex. 1 8 an d 4 5 2 4 an d 3 0 2 24 3 12 30 4 5 15 GCF 6 Ex. 3 3 18 45 6 2 2 0 an d 3 6 20 36 15 2 10 18 5 5 9 GCF 9 2 GCF 4 Notes • Recall • Distributive Property a (b c ) a b ac a (b c ) a b ac When we distribute, all we are doing is multiplying whatever is outside the parenthesis with what is inside. Distribution changes a multiplication problem into an addition or subtraction problem. Notes • Factoring by GCF • Distributive Property BACKWARDS ab ac a b c ab ac a b c When we factor, all we are doing is pulling out the GCF of all terms inside the parenthesis. Factoring changes an addition/subtraction problem into a multiplication problem. Notes Factor. Ex. 2 3x 6x 3 x 3x 2 6x 2 x 2x x 2 3 x x 22 This takes too long. Lets take off the training wheels. Ex. 3x 6x 2 GCF 3 x 3 x x 22 What is the GCF? What number goes in both? What letter goes in both? Now take out GCF. What is left? Notes Factor. Ex. 8 x 12 GCF 4 4422 xx 3 Now you try. Ex. 12 x 30 GCF 6 6 2 x 55 Ex. 2 What is the 7 x GCF? 9x What number G C F goes x in both? xx 7 x 99 What letter goes in both? Now take out GCF. Ex. 3 What 4 xis left? 5x GCF x xx 4 x 2 55 2 Ex. 2 What is5the x GCF? 20 x What number G C F goes 5x in both? 5 x x 44 What letter goes in both? Now take out GCF. Ex. 2 What 4 x is left? 28 x GCF 4 x 4 x xx 77 Notes Factor. Ex. 2 6 x 9 x 12 Ex. 2 x 6 x 10 x 3 GCF 3 33 22xx 233xx44 2 2 GCF 2 x 2 22 xx xx 33xx55 2 Now you try. Ex. 4x 8x 9x 3 2 GCF x x 4 x 88xx 99 2 Ex. 3 2 8 x 12 x 16 x GCF 4 x 4 x 22 xx 2 33xx 44 2 Notes Factor. Ex. Ex. Ex. 5 4 2 6 x 15 x 21 x 8x 4 10 x 14 GCF 4 G C F 2 GCF 3 x2 4 22 xx 11 2 5 x 77 3 x 2 22xx3 55x x2 7 7 2 3 2 Now you try. Ex. Ex. 15 x 5 9 x 15 GCF 5 G C F 3 2 2 5 3 x 1 2 3 33 xx 55 Ex. 5 3 10 x 20 x 45 x GCF 5 x 4 2 55 x 2 x 44xx 99 4 2 Summary The first option to factoring is to take out the GCF Find out which ________ number and/or which _____. variable goes into every term in the parenthesis. Once ________ out Last keep inside you find the GCF then take it ____. parenthesis whatever is left-over. the ___________ Today’s Homework Rules for Homework 1. Pencil ONLY. 2. Must show all of your work. • NO WORK = NO CREDIT 3. Must attempt EVERY problem. 4. Always check your answers. Homework Factor. 1. 5 x 15 2. 6 x 10 3. 4x 7x 4. 2x 6x 5. 8 x 12 x 6. 3x 6 x 6 7. 6 x 8 x 12 8. 7x 5x 4x 9. 4 x 16 x 12 x 2 2 2 3 2 2 2 3 2 10. 4x 8x 6x 11. 6x 3 12. 16 x 8 13. 3 x 12 14. 8 x 12 x 15. 2x 4x 5x 3 2 2 2 5 3 2 Ticket Out the Door Complete the Ticket Out the Door without talking!!!!! Talking = time after the bell! Put your NAME on the paper. When finished, turn your paper face DOWN. Factor. 4 x 12 x 8 2 4 x 3x 2 2